The present invention relates to a yoke structure of a speaker diaphragm, and especially to yoke in a speaker which can be assembled conveniently. The diaphragm thereof is adaptive to the operation of the speaker. Moreover, the output of the speaker will avoid the interfere from the vibration of the diaphragm. Therefore, the work of the yoke portion and the sound wave are more harmonic and as a result, a better sound quality is acquired.
A yoke portion is formed between the diaphragm of a speaker and the frame for supporting the periphery of the diaphragm and for isolating the air flow in the front and rear portion of the diaphragm so that the coil can be moved forwards and rearwards conveniently.
In the conventional speaker, a yoke portion is formed between the supporting frame and the diaphragm. Other than positioning the center of the diaphragm, by the arc design thereof, as the diaphragm moves, the yoke portion may telescopically move for assuring the speaker to emit voice correctly.
However, sound pressure of the speaker is positive proportional to the size of the diaphragm. The prior art yoke portion is exposed from the frame which has the following defects. The diameter of the supporting frame is equal to that of the diaphragm plus with the yoke portion. Therefore, the effective area for arranging a diaphragm is further smaller than the diameter of the supporting frame. Therefore, the output of the sound pressure is confined.
In order to improve the aforesaid defect, as shown in FIG. 1, a prior art design is developed, in which the surface of the diaphragm has no yoke portion, while the foaming pad under the enlarging opening of the supporting frame is connected to the lower portion of the diaphragm so that the sound pressure of the output of the speaker is increased effectively. The foaming pad can be used to replace the prior art yoke portion so as to assist the pull and push actions of the diaphragm so that the sound emitted from the speaker can be outputted normally.
However, in this design, the full opened diaphragm is connected to the foaming pad at the lower side. Other than the outermost edge of the diaphragm, no portion is confined by other elements. Therefore, it is possibly peeled after being used for a long time.
If it is to accurately and steadily position the center of the diaphragm, then another yoke portion must be added at the lower portion, i.e., a further assembly work is necessary. Besides, since an elastic foaming body is placed under the diaphragm, therefore, it is not good in cutting a magnetic field. As a force is applied thereon, it will compress due to the elasticity itself. Therefore, the harmonics of the output sound is effective.
Therefore, the prior art full opened diaphragm remains existing some defects needed to be improved.
Accordingly, the present invention provides a yoke structure of a speaker diaphragm, thereby, the output of the speaker will avoid the interfere from the vibration of the diaphragm. Therefore, the work of the yoke portion and the sound wave are more harmonic and as a result, a better sound quality is acquired without any distortion.
Another object of the present invention is to provide a yoke structure of a speaker diaphragm, wherein the folding edge of the top of the first curved portion is connected and enclosed by the end portion of the diaphragm, and thus, the diaphragm will not peel.
To achieve aforesaid object, the present invention provides a yoke structure of a speaker diaphragm comprising a casing having a front side being installed with an enlarged opening and rear side thereof being installed with a magnetic element; a coil being placed in the magnetic element; a damper being engaged with the coil; a diaphragm being placed at the enlarged opening of the casing and being sticky to the coil, and a diaphragm being placed in the inner side of the enlarging opening of the casing to be adhered to the coil. In the present invention, yoke portion with two layer curved portions is placed between the casing and the diaphragm; the yoke portion is made of elastic material and has a front and rear layer, and the upper and lower sides is formed with bent arcs. As a result, the diaphragm can be assembled conveniently at one time and is adhered well, Moreover, the center thereof can be positioned preferably. Thus, the output of the speaker will avoid interference from the vibration of the diaphragm. Therefore, the work of the yoke portion and the sound wave are more harmonic and as a result, a better sound quality is acquired.